Generally, box blanks with die-cut folding lines are used in the production of external cardboard packages such as so-called baskets, trays, etc. In order to form the external package, the bottom flap/s, the top flap/s, and the side flaps are folded in or folded up, or the like, along the folding lines in a specified sequence and, if required, are secured to the box surfaces located therebeneath by means of adhesive points or the like.
This also relates to the production of a so-called RSC box, for example, which is to be understood as a type of outer packages that are produced from suitable box blanks. The acronym “RSC” in this context stands for “regular slotted carton”. This is a common box structure with four flaps or bottom flaps at the bottom box opening and four flaps or top flaps at the top box opening. For a rectangular cardboard box, the shorter sided bottom flaps or, as the case may be, the shorter sided top flaps, are normally the smaller flaps, which are, in particular, arranged inside the box. The longer sided lengthwise bottom flaps or, as the case may be, the longer sided top flaps defining the box length are referred to as major flaps. The major flaps usually meet at the center of the box, where they can be glued together, for example, with a plastic or water-activated tape.
The box blank is first folded to form the box structure with the top and bottom box openings in each case open, and an overlapping side flap is glued, thereby forming a cuboid that is open on both sides. Then the smaller inside bottom flaps with the shorter sides are folded inward until they are arranged substantially perpendicular to the already connected sidewall. Usually, an adhesive or the like is applied onto the outer surfaces of the correspondingly folded smaller inside bottom flaps. Afterwards, the larger outside bottom flaps, or, more precisely, the major flaps, are folded toward the smaller inside bottom flaps and pressed against them such that the larger outside bottom flaps, or, more precisely, the major flaps, are adhesively connected to the smaller inside bottom flaps.
For certain applications it may be advantageous to rotate the expanded RSC box by 90 degrees or to lay it down flat prior to closing the bottom and top openings such that the two openings are then laterally disposed.
Flaps also have to be closed in the production of other outer packages, such as in the production of so-called side-load boxes, end-load boxes, cartons with only one top flap and/or bottom flap that can in each case substantially cover the entire top opening or bottom opening, respectively, etc.
For closing laterally arranged bottom flaps or top flaps, devices are known, for example, in which the flaps are folded in by stationary folding-in units or folding units, also referred to as so-called folding members, and the flaps are held in this folded-in position, or, more precisely, closed position, by a rail. In particular, outer cardboard packages that are open on one side are transported past the corresponding folding-in unit or folding unit or folding member for this purpose. Closing tools with shutters, levers, or fingers, or the like may moreover be employed in cycle operation.
A packaging machine for wrapping an article group, for example consisting of bottles, into a box blank having folding lines is known from EP 1 471 006 B1, for example. This known packaging machine has a bundle-forming unit, which first places the four side surfaces of the box blank circumferentially around the article group standing on the box blank. The side flaps, which are aligned lengthwise to a conveying direction of the bundle group and the box blanks, are then folded in at right angles with the conveyor track, just like subsequently the bottom flaps and/or top flaps are. The side flap closers, which are clearly discernible in the FIGS. 24 to 26 of EP 1 471 006 B1, are provided for this purpose. These side flap closers are two disk-like elements made of half-sickle shapes arranged at both sides of the package conveyor at about the same height in relation to the conveying direction, which elements rotate in a plane that is parallel to the conveying plane, with the elements being coupled to the drive motor for the package conveyor by means of mechanical drive units in order to allow precision-adjusted synchronization of the rotary movement in relation to the feed movement of the packages. These elements are designed to fold in both the preceding and the succeeding side flaps at the front or back ends of the particular passing outer cardboard packages by an angle of approximately 90 degrees. In order to be able to handle boxes of different-sized formats on one machine, the half sickle-shaped disk-like side flap closers are designed to have two parts, where both parts can be manually twisted relative to each other for the purpose of format adaptation.
Furthermore, DE 20 2005 014 345 U1 discloses an apparatus for packaging articles in a box blank having folding lines with side flaps, top flaps and/or bottom flaps, with a device for feeding an article stream; a device for dividing article groups; a device for feeding individual box blanks in conveying direction of the article groups, with the box blanks being transported in a consecutive row from below to be placed underneath the article groups, and the side flaps running pointing lengthwise to the conveying direction; and a device for forming an external cardboard package as well as for folding in the side flaps transversely to the conveying direction by means of folding-in units rotating about an axis that is perpendicular to the conveying plane of the box blanks. The folding-in units are designed as rod-shaped fingers and in each case aligned pairwise at right angles with the perpendicular axis, and they are arranged at approximately right angles, offset in relation to each other in circulation direction, with one finger folding in the side flap located at the rear end of the preceding external cardboard package and the second finger folding in the side flap located at the front-facing end of the succeeding external cardboard package.
The patent application publications DE 10 2010 015 865 A1 and DE 10 2015 107 630 A1 each describe a device and a method for packaging articles in a box blank having folding lines with side flaps and/or top flaps and/or bottom flaps, with the device likewise having folding members for folding over or folding in the side flaps.
For cycle operation with a plurality of external cardboard packages being conveyed from station to station, it would be necessary to dispose stationary folding members between the stations. In cycle operation, however, the transport speed is usually greatest between the individual stations. Additionally, folding in the side flaps in this intermediate area would thus require extreme speeds of the folding members, or else the outer cardboard packages would be required to have large spacings between them in order to provide sufficient time and space for the folding-in procedure. Processing a plurality of outer cardboard packages simultaneously will require a corresponding number of closing tools. A device is moreover necessary that holds the side flaps closed while the outer cardboard packages move on.
The folding-in devices known from prior art require manual adjustments and resetting operations in the instance of the dimensions of the articles and/or boxes to be folded in being changed. Further problems can arise from the relatively complex movement curves that the folding-in devices have to trace in order to be able to fold at nearly the same time two outer cardboard packages being fed one after the other. In addition, the spaces between the boxes can vary according to the pitch of the main conveyor chains. Very small chain pitches in the direction of movement together with very long outer cardboard packages result in relatively small spaces and therefore only very short time slots for folding in the side flaps. Kinematic limits may repeatedly ensue.